Cortical parvalbumin-positive neurons: Functional and ontogenetic characteristics and their relationship to brain...

Cortical GABAergic interneurons can be classified based on electrophysiological, biochemical, and morphological criteria. Among them, parvalbumin-positive interneurons primarily exhibit chandelier and basket cell morphologies and are characterized by a fast-spiking firing pattern. These cells originate from the medial ganglionic eminence during human brain development and are widely distributed across neocortical layers I-VI, with a predominance in layers II and III. Their distinct morphology, extensive axonal arborization, and specific synaptic contacts position them as key regulators of pyramidal neuron activity through axo-axonal and perisomatic inhibition. Parvalbumin-positive interneurons have been extensively studied in the context of neurological and psychiatric disorders associated with excitation/inhibition imbalances, including traumatic brain injury, epilepsy, autism spectrum disorder, and schizophrenia. Given the growing body of evidence, this review provides an in-depth examination of the pathophysiological roles of parvalbumin-positive interneurons, highlighting their selective vulnerability to various types of neural insults.